Experimental studies on hatching behavior in the chick. I. Thoracic spinal gaps.
D000818:Animals; D002642:Chick Embryo / Q000254:growth & development / Q000502:physiology*; D006257:Head; D006614:Hindlimb; D009068:Movement / Q000502:physiology*; D012399:Rotation; D013116:Spinal Cord / Q000502:physiology*; D014921:Wings, Animal